Water-tube boiler



Aug. 20, 1929. Q a UNDSTROM 1,725,463

WATER TUBE BOILER Filed 1924 2 Sheets-Sheet l m unn gwumtoa 5m azmszzm,

Aug. 20, 1929. c. B. LINDSTROM WATER TUBE BOILER Fil d v- 1924 2Sheets-Sheet 2 gwventoc ooooo amzzmzazwn,

Patented Aug. 20, 1929.

.UNITED STATES CLAUDE B. LINDSTROM, OF COSCOB, CONNECTICUT.

WATER-TUBE BOILER.

Application filed November 11, 1924. Serial No. 749,166.

This invention relates generally to water tube boilers, an object ofwhich is to provide boiler construction which combines the advantageousfeatures of both the vertical and horizontal water tube boilers now inuse.

A further object of the invention is to so combine these features toenable the construction of boilers of larger capacities.

A still further object is the combination fire box and water tube boilerhaving baffles so arranged as to obtain greater benefit of heat unitsfrom the fire box than has heretofore been possible, the constructionpermitting of the effective and economical use of fuels such as oils andcheaper grades of bituminous coals with a minimum of smoke waste.

A further object is the provision of the novel staying means hereindisclosed for rigidly maintaining the boiler sections in proper positionand against distortion incident excessive temperatures and high internalpressures.

WVith these objects in view, together with others which will appear asthe description proceeds the invention consists in the novelconstruction, combination and arrangement of parts, all as will bedescribed more fully hereinafter, illustrated in the drawings, and

particularly pointed out in the claims.

In the drawings:

Fig. 1 is a longitudinal sectional view taken through a boilerconstructed in accordance with the invention,

Fig. 2 is a fragmentary front elevation of the structure shown in Fig.1,

Fig. 3 is a fragmentary side elevation of a boiler of slightly modifiedform, and

Fig. 4 is a fragmentary front elevation of the structure disclosed inFig. 3.

This combination fire box and water tube boiler includes inner and outercasings 5 and 6 respectively, the inner casing including the fire boxand combustion chamber. The casing 5 is provided with a convex crownsheet 7 with depending side walls or sheets 8, and to resist pressurethe crown sheet may be stayed or reinforced with bars 9 at properintervals securely welded in place. These bars are preferably providedwith spaced openings 10 to permit of proper circulation of water in theboiler.

The forward portion of easing 8 is provided at its bottom with the usualgrate 11, at the rear end of which rises the usual bridge wall 12, andstoking is carried out. through the door opening indicated at 13.

The outer shell or casing 6 properly oncloses the inner casing andprovides a substantially large chamber 14 at the upper end of the boilerand spaces providing water legs 15 at both sides and at the front andrear of the boiler. The front and rear heads of the outer casing aresuitably braced by means of stays 16, and the two casings are rigidlysecured together by a series of Ttays 17 arranged within the severalwater egs.

It will be understood that suitable leadin and take-off pipes may beconnected with the boiler at proper and suitable places. It will also beunderstood that the connection of the heads with their respective innerand outer casings will be made in accordance with the uses to which theboiler will be subjected, and these connections may be carried out byfianging and riveting or may be welded for low pressure boilers.

The inner casing 5 is provided with a pluralit-y of tubes arrangedvertically, and in such manner as to obtain maximum efficiency from thefuel employed. These tubes are indicated at 18, and are arranged inspaced parallel relation from one end to the other within the innercasing. The tubes 18 are disposed vertically within this casing andestablish communication between the chamber 14 at the upper part of theboiler and the water legs 15 at the sides of the boiler. The tubesextend well down into the fire box so that the lowermost of said tubesare disposed relatively close to the fire bed. The tubes are preferablyarranged in banks; the lower ends of the tubes of each bankcommunicating with the adjacent water legs at the sides of the boiler.The outer Wrapper or casing 6 is provided with openings closed bysuitable caps 19 in alignment with the lower ends of tubes 18, to permitof cleaning the tubes or repairing them when necessary.

The bridge wall 12 has rising therefrom a baffle 20 of suitablerefractory material, which is of a breadth equal to the width of theinner casing 5, while rearwardly beyond this baflie is arranged asimilar depending bafile 21, secured at its upper end to the crownportion of the casing 5. The baffle 20 has its upper end disposed belowthe top of easing 5, while baffle 21 terminates well above the bottom ofthe combustion chamber, so that the products of combustion rising fromthe fire box musttake a circuitous path around the ballles andincidentally in intimate contact with the tubes 18 before escapingthrough the smoke pipe 22.

It is apparent that this structure provides an enlarged combustionchamber hav ing the water tubes so associated therein that a maximumdegree of heat will be obtained from the fuel consumed, and by reason oithis enlarged combustion chamber the more or less volatile fuels may beeliectively used.

The structure disclosed in 3 and i is the same as that heretoforedescribed, except that the vertical baiiies are dispensed with, ahorizontal baiilc is employed and the smoke pipe is disposed at theforward end of the boiler. In this form of the invention, a horizontalbatl'le 23 of refractory material disposed well above the bridge wal 12,and terminates at its rear end a substantial distance inwardly from therear head of the inner casing. The smoke pipe communicates with theinner casing near the upper portion thereof and immediately above thehorizontal plane of ballle v In this form of the invention the productsof combustion pass from the fire box rearwardly over the bridge wall 12and in close contact with thevarious water tubes, then around the rearend of battle 23 and pass forwardly through the banks of tubes to thesmoke escape pipe 22. By providing this enlarged area within the casing,it is apparent that thorough combustion and burning of the gases withinthe inner casing will occur before the waste eventually passes throughthe smoke pipe.

It Will be understood, of course, that any preferred ,or desired meansfor securing the crown and side sheets to the heads: may be employed,and any preferred method or manner of arranging the tubes and connectingthem at their respective ends with the crown and side sheets of theinner casing may be used. It will be understood, furthermore, that thebanks of tubes diverge at their lower ends so that communication betweenthe compartment 14 and the water legs on each side of the boiler isassured.

Having thus described my invention, I claim:

In a boiler, outer and inner casings having their walls spaced apart toprovide an upper Water and steam compartment and water legs on all sidesof the boiler, tubes arranged in banks in said inner casing andestablishing communication between said upper compartment and said waterlegs, each tube having right angularly disposed portions connected by agradual bend and one oi said portions longer than the other, the longerportions of said tubes connected with the said upper compartment anddisposed vertically while the shorter portions of said tubes aredisposed horizontally and connect with said water legs, said banksextending throughout the length of the inner casing and in the path ofthe products of combustion in the latter, the tubes of each bank beingof equal length and parallel to each other and the said banks spacedequal distances apart, and bafiles among said tubes to cause theproducts of combustion to take a sinuous course therethrough.

In testimony whereof I afiiX my signature.

CLAUDE B. LINDSTROM.

